Polaris motor swap help please!

[big10champ2003]

Has anybody done this / or does anybody know if it is possible to swap a '90 polaris fuji 500 motor into a '03 600 rmk chasis?

I found a good rolling chasis ('03 rmk 144) that I was thinking I coud swap the motor from a '90 indy 500 I have, which I know the motor runs like a champs and is bullet proof. It would make a great sled for my son. I am just not sure if everything will fit properly.

If you have done something like this, or know whether it will or will not work I could us some input. Mostly wondering if the motor mounts and clutching will line up. Also if the exhaust will fit. I can get the electrical to work.

 

[jimfsr]

A project like that is possible. I have done swaps from year to year, one manufacturer to another, and custom built entire chassis around a motor. The question is how is your fabrication skills?
1- will the motor physically fit in the chassis-probably, take few basic measurements of the engine height and width
2-clutch alignment is the most critical. the belt length can be variable if you check the dimensions of available belts. If the stock widths are the same from the old one to the new you should be fine, if there is a difference most modern secondary clutches give provision for width adjustment. the distance between is the one you cannot change. the experimental part comes when the belt is all the way up in the primary it MUST be all the way down in the secondary, if there is still room for the secondary to open more you could throw the belt off the primary and then you have a mess.
3 -fab the mount to get the motor where you want it so the clutches will work. You will probably have to make the holes very generous until you are sure of the positioning, then you can re-fab the mount to fit where it needs to be. Don't forget the torsion bumper when the mount is finalized.
4- figure out the airbox , will the stock one work? can you make the one from the 500 fit? More fab time! You can use KN type filters if needed but will have to re-jet for them
5- electronics-good mounting spot that wont get hot
6-this will be the biggest challenge-exhaust. No the stock 500 will not fit in the chassis of the new one. No you cant swap an exhaust off a 600 and make it work. You must maintain the internal dimensions of the stock pipe to allow the motor to breath as it was designed to. You can cut and twist the pipe as needed to fit, but cannot shorten or lengthen the chamber or stinger. You can cut the muffler off the stock 500 exhaust if it is incorporated into the headpipe (most were back then) the tuned chamber and stinger are inside the rear part of the assembly. mufflers are not as critical so how that gets fabricated is up to you. There may be some minor power changes with different mufflers, but much less of an affect than altering the chamber and stinger.

Good luck and let me know if there are more issues that crop up. I would like to see pix of the project if you do it.